SPI with display modules in Raspberry Pi - Mini Project: Build & Apply

SPI Communication with a Display Module on Raspberry Pi

📖 Scenario: You have a Raspberry Pi connected to a small SPI display module. You want to send simple messages to the display using SPI communication.This project will guide you through setting up SPI communication, configuring the display, sending data, and showing the message on the display.

🎯 Goal: Build a Python program that sends a message to an SPI display module connected to your Raspberry Pi and shows the message on the screen.

📋 What You'll Learn

Use the spidev library to communicate over SPI

Create a message string to send

Send the message bytes over SPI

Print confirmation that the message was sent

💡 Why This Matters

🌍 Real World

SPI is a common way to connect small displays to microcontrollers and single-board computers like Raspberry Pi. This project shows the basics of sending data to such displays.

💼 Career

Understanding SPI communication and how to send data to hardware devices is important for embedded systems, IoT development, and hardware interfacing roles.

1

Set up SPI communication

Import the spidev module and create an SPI object called spi. Then open SPI bus 0, device 0 using spi.open(0, 0).

Raspberry Pi

import spidev

# Create SPI object and open bus 0, device 0
# Your code here

Hint

Use spidev.SpiDev() to create the SPI object and open(0, 0) to select bus 0 and device 0.

2

Configure SPI speed

Set the SPI maximum speed to 500000 (500 kHz) by assigning spi.max_speed_hz = 500000.

Raspberry Pi

import spidev

spi = spidev.SpiDev()
spi.open(0, 0)

# Set SPI max speed to 500000 Hz
# Your code here

Hint

Assign the value 500000 to spi.max_speed_hz to set the speed.

3

Send a message string over SPI

Create a variable called message with the string 'Hello SPI Display'. Then send the message bytes over SPI using spi.xfer2(list(message.encode())).

Raspberry Pi

import spidev

spi = spidev.SpiDev()
spi.open(0, 0)
spi.max_speed_hz = 500000

# Create message variable and send it over SPI
# Your code here

Hint

Use message.encode() to convert the string to bytes, then convert to a list for xfer2.

4

Print confirmation message

Print the text 'Message sent to SPI display.' using print().

Raspberry Pi

import spidev

spi = spidev.SpiDev()
spi.open(0, 0)
spi.max_speed_hz = 500000

message = 'Hello SPI Display'
spi.xfer2(list(message.encode()))

# Print confirmation message
# Your code here

Hint

Use print('Message sent to SPI display.') to show confirmation.